Winston Churchill's bodyguard had his share of dangerous moments. But his job gave him a unique insight into the great man's strengths and flaws — as recently unearthed memoirs reveal

No great man, they say, is a hero to his valet. A bodyguard, who oversees his charge pitilessly night and day, might be expected to have a yet lower opinion. Walter Thompson, a protection officer from Scotland Yard, spent almost 18 years guarding Winston Churchill, from 1921 to 1945, with a break in the 1930s. His presence was so constant that, as he ruefully admitted, he became a "perpetual annoyance" to Churchill's wife, Clementine.

He was outside the door of every room her husband was in. He ate and slept at the Churchills' houses in London and at Chartwell in Kent, and then at Downing Street and in their Blitz-proof quarters in the annexe. He travelled with "the Old Man" so often that his own marriage was wrecked, protecting him from potential assassins, helping him through "the Black Dog" of his depressions, caring for him when he was ill and